import 'dotenv/config'
import { createServer } from 'http';
const PORT = process.env.PORT;
// 模拟⽤户数据
const users = [

 { id: 1, name: '张三' },
 { id: 2, name: '李四' },
 { id: 3, name: '王五' }
];

const logger=(req,res,next)=>{
    console.log(`&{req.method} ${req.url}`);
    next();
};

const jsonMiddleware = (req, res, next) => {
    res.setHeader('Content-Type', 'application/json;charset=utf-8');
    next();
   };


const getUsersHandler = (req, res) => {
    res.write(JSON.stringify(users));
    res.end();
   };
   // 路由处理 GET /api/users/:id
    const getUserHandler = (req, res) => {
    const id = req.url.split('/')[3];
    const user = users.find(user => user.id == id);

    if(user) {
        res.write(JSON.stringify(user));
    } else {
        res.statusCode = 404;
        res.write(JSON.stringify({ message: '⽤户不存在' }));
    }
    res.end();
   };
   // 路由处理 404
   const notFoundHandler = (req, res) => {
        res.statusCode = 404;
        res.write(JSON.stringify({ message: 'API不存在'}));
        res.end();
   }


   const createUserHandler = (req, res) => {
        let body = '';
    // 监听'data'事件，逐块接收请求体的数据
        req.on('data', (chunk) => {
        body += chunk.toString();
    });
    // 数据接收完毕后，触发'end'事件
    req.on('end', () => {
        const user = JSON.parse(body); // 解析请求体中的JSON数据
        users.push(user); // 将解析出的⽤户添加到⽤户列表中
        res.statusCode = 201; // 设置响应状态码为201，表⽰创建成功
        res.write(JSON.stringify(user)); // 返回创建的⽤户数据
        res.end();
    });
   };

   const server=createServer((req,res)=>{

        logger(req,res,()=>{
            jsonMiddleware(req,res,()=>{
                if(req.url==='/api/users'&&req.method==='GET'){
                    getUsersHandler(req,res);
                }else if(req.url.startsWith('/api/users')&&req.method==='GET'){
                    getUserHandler(req,res);
                }else if(req.url==='/api/users'&&req.method==='POST'){
                    createUserHandler(req,res);
                }else{
                    notFoundHandler(req,res);
                }
            })
        })
   })
// 服务器监听端⼝号，且启动成功后输出提⽰信息
server.listen(PORT, () => {
    console.log(`服务器已启动，监听端⼝${PORT}`);
});